Re: [PATCH net-next] gtp: annotate PDP lookups under RTNL

[Simon Horman <horms@kernel.org>]

On Wed, Jul 01, 2026 at 08:39:25PM +0800, Runyu Xiao wrote:
> The GTP PDP lookup helpers are shared by RCU-protected data and report
> paths and RTNL-protected control paths such as gtp_genl_new_pdp(). The
> helpers walk RCU hlists, but they do not currently pass the RTNL
> condition for the control-path lookups.
> 
> Pass lockdep_rtnl_is_held() to the PDP hlist iterators. Existing
> RCU-reader callers remain valid because the RCU-list macros also accept
> an active RCU read-side section; the added condition only documents the
> non-RCU protection already used by RTNL control paths.
> 
> This was found by our static analysis tool and then manually reviewed
> against the current tree. The dynamic triage evidence is a
> target-matched CONFIG_PROVE_RCU_LIST warning; the change is limited
> to documenting the existing protection contract.
> 
> This is a lockdep annotation cleanup. It does not change PDP lifetime or
> hash updates.
> 
> Signed-off-by: Runyu Xiao <runyu.xiao@seu.edu.cn>

Reviewed-by: Simon Horman <horms@kernel.org>

There is an AI-generated review of this patch available on sashko.dev.
While I don't believe that the issues raised there should impede progress
of this patch you may want to look into them as possible follow-up.

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